touch tablet paint program ui thoughts

I do daydream about making an expanded version of my self-published comic on coping with mortality, something that captures the best of my thinking not just on death but on the best way to get through life. 

I continue to look for the best app to do that with, experimenting with various paint programs (over the year I've spent so much money on devices with touch sensitive screens, each time thinking "maybe THIS will be the one that lets my doodle skills blossom") Apple iPad's "Notes" program probably can't be it (if only because it doesn't deal with layers) but it really has some interesting UI decisions: coloring with the marker is more or less two-toned, paint once then start painting on the same spot to get a darker shade. And the eraser tool is kind of wild: it's like using the "Undo" button (that might erase a set of lines squiggles you made without lifting the stylus all at once) but instead of removing the last thing you did, it removes what ever you poke with the eraser tool. It's disconcerting at first, but kind of encourages a "well if you mess up you can do that whole thing over" approach.

I'm appropriately humble about my doodle skills, but looking at the sesame street characters I drew from memory during a meeting, I wonder if some of the lack of depth most of my stuff has comes from my preferences for using flat flood fill to color with... it's interesting to let go of a kind of "coloring perfectionism". 

UPDATE: Like I said, the way this app implements "erase" (stroke based and "undo"-like instead of merely removing pixels from a location on the screen) is amazing - I've never seen its like. Some other UI bits are not so good and I had to google for them... 
1. if you have a note that's just "handwriting" / drawing, it's not clear how to name it - while editing it, you pull the main canvas down, and then there's a place to edit it.
2. moving a note to a folder is weird, looking at the list of notes you have to swipe the note name to the side and then it's one of the three options, along with lock and delete.
3. Finally, there's some kind of cool "graph paper" backgrounds (or just lines, which might be useful for handwriting words) which you access via the icon that's usually share... I guess if you start with a pristine note you have that option of "Lines & Grids" but once you start drawing the widget reverts to "send to" mode... kind of weird.

Those first two things are at the heart of why I don't feel confident doing serious work on the iPad... I guess there's this "Files" app that might be coming up to speed, but the conventions for file management are really wonky relative to MacOS or even Windows. (And the third thing is another general problem for iOS that Gruber talks about all the time - there's nothing that matches the discoverability and power of the desktop menu bar, no universal, cross-app way to browse through ALL the commands you have handy, so every app has to work it out for itself.